As water is produced from an aquifer such as the Ogallala at a rate that is higher than the aquifer is being recharged by natural processes, the water saturated thickness of the aquifer decreases. Beyond a critical value of saturation thickness, the maximum rate widhdrawn from a well decreases proportionally. This value is directly related withdrawn from a well decreases proportionally. This value is directly related to the rate in gallons per minute of water withdrawal that is required, and inversely related to the permeability of the aquifer. When the pumping rate is increased beyond such critical value, air breaks through the water-air interface at the top of the water saturated zone and curtails water production. When break-through occurs, both air and sand or other sediments can flow to the pump and cause serious damage to it. Thus as the water saturated thickness of an aquifer that is not being naturally recharged in a sufficient manner decreases with time, the well operator is forced to reduce the water production rate, which for crop irrigation reduces the number of acres that can be farmed. When the well is used as a municipal supply, water use must be curtailed by rationing. Eventually, additional water wells will have to be drilled, completed, and put on production to provide the required supply of water. In most cases the drilling and completion costs and the additional power requirements for additional wells make the economics questionable.
It has been recognized, for example in connection with the Ogallala aquifer which accounts for about 30% of the national supply of ground water used for agricultural irrigation, that its water saturated thickness has been declining for many years. See Weeks et al, "Summary Of The High Plains Regional Aquifer-System Analysis In Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas and Wyoming" USGS (1988). From this report it can be recognized that the average water production needed may require a doubling of the number of wells in order to sustain an agricultural area, over the coming 25 year period. The ground water source over a seven county area of Texas was at its critical saturation thickness as far back as 1956. Indeed nearly one-half of the Ogallala aquifer throughout the eight states covered by the Weeks' report had less than 100 feet of saturated thickness left in 1980. Heretofore, the only solution to the problem of reduced water production rates has been to drill, complete and put on production more wells, which will involve very large cost outlays that may not be economically feasible.
A general object of the present invention is to provide a new and improved agricultural, commercial or municipal utility district water well completion method which will extend the producing life of a recharge-deficient aquifer.
Another object of the present invention is to provide a new and improved water well completion method where water entry into the well bore is over a horizontal or near-horizontal section thereof which substantially reduces the possibility of air breakthrough, thereby increasing the maximum flow rate of a single well.